The TV upfronts are an exercise in the art of obfuscation, or framing, or simple B.S., as my colleague Matt Belloni recently wrote. Media companies are selling advertising agencies and Fortune 100 C.M.O.s on the idea that their series, or platform, is the most brand-safe, or the most Gen Z-friendly, or the best place for allergy medication spots. Indeed, this was all much easier when the media industry agreed upon a simple medium (linear) and there was one analytics platform (Nielsen), which informed ad spend better than just about anything else. You could simply look at the 8 p.m. slot on Wednesday and see that, yes, Dick Wolf was still TV’s magnetic draw. 

Of course, Netflix upended all this and brought the transformation full circle last week with its first appearance at the upfronts, albeit via a virtual showcase, touting some strong numbers for its advertising tier, which only launched six months ago. Netflix’s main argument coalesced around 5 million global monthly active users, but… five million of what exactly? 

In retrospect, it wasn’t entirely clear what the company has achieved. Netflix either added 5 million customers or 5 million monthly active users. A subscription is measured per account (like subscriber figures presented in financial earnings). Monthly active users effectively include all profiles watching on one account. This is key to ensuring that ads aren’t shown on children’s profiles. The difference may seem pedantic, but the breakdown of those users within the advertising tier, including whether or not they descended from the ad-free tier or were net new subscribers, is key to understanding the platform’s momentum.